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When to plant Crosne in Johnson County, IL

In Johnson County, plant Crosne in spring between March 24 and April 14, once soil temps hold above 50°F. Johnson County's last frost averages April 7, so most warm-season crops establish quickly once soil holds above 60°F. For a fall crop, sow between August 12 and August 26 — roughly 150–200 days before the first frost on October 21.

When to Plant Crosne in Johnson County, IL

Crosne (Chinese artichoke) produces small, segmented white tubers with a crunchy texture and mild artichoke-nutty flavor. They are a rare delicacy in French cuisine.

Johnson County, Illinois is in USDA Zone 7a. The average last spring frost is April 7 and the first fall frost is October 21, giving you a growing season of approximately 197 days.

At an elevation of 1,006 feet, Johnson County receives approximately 39.7 inches of rainfall annually with predominantly silt loam soil. Summer highs average 90°F, providing good warmth for Crosne during the growing season.

Johnson County, IL (Zone 7a) Moderate season
197 days
Last Spring Frost April 7
197 growing days
First Fall Frost October 21

Johnson County Soil Profile

Soil Type

Silt Loam

Soil pH

5.9-7.2

Drainage

Well Drained

Monthly Watering Guide for Crosne

Crosne needs approximately 1 inches of water per week (4.3" per month). Here's how your county's rainfall compares month by month.

Month Crosne Needs Rainfall You Supplement Action
Jan 1.6" 0" ❄️ Dormant
Feb 1.9" 0" ❄️ Dormant
Mar 2.9" 0" ❄️ Dormant
Apr 4.3" 3.6" 0.7" 💧 Light watering
May 4.3" 4.2" 0.1" 💧 Light watering
Jun 4.3" 4.4" 0" ✅ Rainfall sufficient
Jul 4.3" 4.8" 0" ✅ Rainfall sufficient
Aug 4.3" 4.6" 0" ✅ Rainfall sufficient
Sep 4.3" 3.3" 1" 💧 Light watering
Oct 4.3" 3.2" 1.1" 💧 Light watering
Nov 2.9" 0" ❄️ Dormant
Dec 2.3" 0" ❄️ Dormant

Water needs are for active growing months only (Apr–Oct in Johnson County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.

Crosne Planting Timeline — Johnson County, IL

Crosne Planting Calendar

Activity When Date Range
Direct Sow March 24 Mar 24 – Apr 14
Harvest August 25 Aug 25 – Oct 27
Fall Sowing August 12 Aug 12 – Aug 26

Plant 0.5" deep · 6" apart · Rows 12" apart

Month-by-Month Timeline

MonthActivities
January
February
March Direct Sow
April Direct Sow
May
June
July
August Fall Sowing Harvest
September Harvest
October Harvest
November
December

Growing Conditions

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

Moderate — regular watering

📅 Days to Maturity

150–200 days

🧪 Soil pH

Needs 6–7 · Your soil: N/A

🗺️ USDA Zone

Zone 7a

📆 Growing Season

197 days in Johnson County

Growing Tips for Johnson County

Plant tubers 3 inches deep in spring. Mark the location well as plants die back. Harvest in late fall after frost. Leave some tubers in ground for next year. Very labor-intensive to harvest.

Companion Planting

Good Companions

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Crosne in Johnson County, IL?

Johnson County is in Zone 7a with an average last frost of April 7. Plan your Crosne planting based on this frost date — see the calendar above for exact timing.

What planting zone is Johnson County, IL?

Johnson County, Illinois is in USDA Hardiness Zone 7a. The average last spring frost is April 7 and first fall frost is October 21.

When should I plant Crosne in Johnson County, IL?

In Johnson County, IL, plant Crosne after the last frost (around April 7) and before the first frost (around October 21). Best results when soil holds above 50°F.

What growing zone is Johnson County, IL for Crosne?

Johnson County sits in USDA Zone 7a. Crosne grows reliably in zones 4a through 9b, so it's a good fit here.

Can Crosne grow in Johnson County's climate?

Yes — Crosne grows well in Johnson County's temperate climate. Johnson County averages a 197-day frost-free season, with last frost around April 7 and first frost around October 21.

🌱

Your Johnson County Garden Planner — Free

A 22-page printable planner built for Johnson County (Zone 7a). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.

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Data sources: USDA Plant Hardiness Zone Map (2023), NOAA 30-Year Climate Normals. Frost dates are based on 50% probability averages for Johnson County, IL. Local conditions may vary. Last updated: July 2026.

Sources & credits

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